Antenna having concealed lightning arrester



Sept. 8, 1953 E. FINKEL 2,651,720

ANTENNA HAVING CONCEALED LIGHTNING ARRESTOR Filed March 15, 1950 INVENTOR. EM/vq FNKEL B) A TOIQNEY Patented Sept. 8, 1953 ANTENNA HAVING CON CEALED LIGHTNING ARRESTER Edward Finkel, Brooklyn, N. Y., assignor to J. F. D. Manufacturing 00., Inc., Brooklyn, N. Y., a corporation of New York Application March 13, 1950, Serial No. 149,246

3 Claims.

This invention relates to high frequency television and frequency modulation antennas.

It is customary to include lightning arresters in aerial installations for television and frequency modulation broadcast receivers. Said arresters, in addition to providing a non-destructive path to ground for very high voltages, function to improve reception by leading to ground static charges that may accumulate on the aerial. For

the latter reason particularly they are considered highly desirable in television installations wherein imperfections in signal reception are a source of considerable annoyance.

Heretofore, the installation of lightning arresters has been attended by marked disadvantages. For example, mounting and wiring the arresters required time and increased the initial cost of installation. Moreover, since lightning arresters had to be adapted to withstand outdoor weather conditions, they were necessarily costly. Further, lightning arresters were unsightly and required exposed wiring between the arresters and the aerials as well as between the arresters and ground.

It is the principal object of the present invention to eliminate the above-mentioned difilculties.

More specifically, it is a primary object of the invention to provide a unitary device which will function both as an antenna and as a lightning arrester.

A further object of the present invention is to provide a device of the character described in which the lightning arrester is concealed.

Another object of the invention is to provide a device of the character described which is not unsightly.

Other objects of the invention will in part be obvious and in part will be pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements and arrangements of parts which will be exemplified in the devices hereinafter described and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings in which are shown various possible embodiments of the invention,

Fig. 1 is a perspective view of an aerial installation including an antenna and lightning arrester combination embodying the present invention;

Fig. 2 is an enlarged sectional view taken substantially along the line 22 of Fig. 1;

Fig. 3 is a sectional view taken substantially along the line 33 of Fig. 2;

Fig. 4 is a longitudinal sectional view through the lightning arrester shown in "Fig. 1;

Fig. 5 is a fragmentary front view of an antenna and lightning arrester combination embodying a modified form of the present invention;

Fig. 6 is a sectional view taken substantially along the line 6-6 of Fig. 5; and

Fig. 7 1s a plan view of a carbon resistor used as the lightning arrester oi the combination shown in Fig. 5.

Referring now in detail to the drawings, and

more particularly to Figs. 1-4, the reference numeral l0 denotes a device embodying the present invention. Said device includes an antenna l2 and a lightning arrester l4.

The antenna comprises a rigid metallic driven element iii of any type well-known in the art. For example, a pair of quarter-wave length dipoles may be employed. In the antenna shown In the drawings, the driven element constitutes a double-V dipole having quarter-wave length metallic rods [6 arranged in pairs liia, 16b. These rods define a pair of acute angles which are opposed to one another, and are inclined slightly forward in the direction of the incoming signal.

A pair of electrically conductive clamps l8 serves to hold the rods in the foregoing position. Each clamp comprises a metallic front plate 20 and a companion back plate (not shown). The rods are held between these plates by nuts and bolts 2|. One plate of each clamp, e. g. the front plate 20, is secured, for instance, by nuts and bolts 22, to spaced portions of a rigid block 24 of electrical insulating material that acts as part of a support for the driven elemnt. It thus will be apparent that the rods it on either side of the block are electrically interconnected and are insulated from the rods on the other side of the block.

The block is attached, as by nuts and bolts 26, to a U-shaped bracket 28 which is insulated by said block from the clamps and the driven element 15. Said bracket is aflixed, as for example by rivets 29, to a hollow metallic tubular crosspiece 30. A metallic clamp 32 serves to secure said crosspiece adjacent its center to a metallic mast 34. The latter is fastened in any conventional manner to a support and is suitably grounded, as by a wire 36.

From the foregoing it will be appreciated that the antenna support includes the block 24, the crosspiece 30 and the mast 34. As will be understood to skilled workers in the art, the crosspiece may be omitted if no reflector is employed. Pursuant to the invention, all the metallic components of the support are grounded.

At the end of the crosspiece remote from the driven element, a reflector of any standard type may be mounted. The reflector shown in the drawing has four rods spaced similarly to those of the driven element, except that the rods are not forwardly inclined. Moreover, the insulating block is replaced by a metallic member which electrically interconnects all the reflector rods.

The lightning arrester l4 constitutes a pair of an well-known compact current blocking devices, for instance a pair of glow tubes 56. Said tubes are contained in an insulating sleeve 38 the ends of which are closed as by plugs 39 of wax or pitch. The tubes comprise glass envelopes having an interior ionizable gas atmosphere. Each tube has two leads 42 running from spaced electrodes within the envelope so that current will not flow through the tube until the impressed voltage is high enough to ionize the gas therein. Each tube has one lead thereof connected by an insulated wire it to a diiierent one of the-pairs of rods it, said wires optionally being attached by the nuts and bolts 22 holding the clamps to the insulating block. Wires 46 run from the other leads of both tubes through an opening 8 on the underside of the crosspiece 38 to any suit- 1 able attaching point on a conductive part of the antenna support, e. g. the crosspiece. More specifically, the wire 46 is attached to the rivet 29 that holds the bracket 28 to the crosspiece. In the embodiment shown, the lightning arrester is disposed within the hollow crosspiece at the end thereof near the driven element. However, it may be located anywhere in the crosspiece or in the mast, it being understood that the electrical connection would remain the same. 7

A modified form of the invention is shown in Figs. -7 wherein parts similar to those shown and described in Figs. 1-4 are denoted by like numerals primed. In this latter form the two current blocking devices of the lightning arrestor comprise a pair of high resistance, e. g. one megohm, carbon rod resistors 52 received in slots 53 in the front face of the block 2%. Each resistor has one end thereof secured to a clamp it, as by the nut and bolt 22, and the other end attached to a conductive portion of the antenna support, e. g, to the crosspiece as by the nut and bolt 26. The resistors desirably are covered by sealing wax or a similar mastic substance. Thus a high resistance leakage path to ground is provided for static voltage from each of the two mutually insulated portions of the driven element of the antenna.

The glow tube type lightnin arrester provides in efiect an absolute current block between the driven element of the antenna and the grounded antenna support. However, when static voltage builds up high enough on the driven element, the glow tube will become conductive and permit the charge to be led to ground. As above noted, the carbon resistors provide a steady but minute leakage path to the grounded antenna support for static voltages on the driven element but constitute an efficacious current block to voltages of the low amplitude of television or frequency modulation signal voltages which, accordingly, are not noticeably weakened.

It will be seen that by incorporating a lightning arrester in combination with an antenna support not only is the independent mounting and connection of the arrester eliminated but the arrester itself can be of greatly simplified construction since it is not necessary for it to include its own mounting means and wire terminals and since its weatherproofing and protective features may be done away with.

It thus will be seen that there are provided devices which achieve all the objects of the invention and are well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In a high frequency television or frequency modulation antenna receiver installation which includes an electrically conductive mast and. a rigid metallic driven element constituting at least two spaced members, a unitary device comprising a support for said driven element, said support including a rigid block of electrically non-conductive material, a pair of electrically conductive means detachably securing the members of said driven element to said block in mutually spaced relationship, an electrically conductive crosspiece adapted to be detachably secured to the mast in electrical connection therewith, and means securing the crosspiece to the block in spaced relationship to the members, said support having a slot opening on the external surface thereof; a lightning arrester disposed in the slot in said support, means closing the slot and covering the lightning arrester disposed therein, said lightning arrester including a pair of carbon resistors; and means electrically connecting one end of one of said resistors to one of said member-securing means and one end of the other of said resistors to the other member-securing means, and means electrically connecting the other ends of both of said resistors to said crosspiece.

2. In a high frequency television or frequency modulation antenna receiver installation which includes an electrically conductive mast and a rigid metallic driven element constituting at least two spaced members, a unitary device comprising a support for said driven element, said support including a rigid block of electrically nonconductive material, a pair of electrically conductive means detachably securing the members of said driven element to said block in mutually spaced relationship, an electrically conductive crosspiece adapted to be detachably secured to the mast in electrical connection therewith, and means securing the crosspiece to the block in spaced relationship to the members, said block having a slot opening on the external surface thereof; a lightning arrester disposed in the slot in said block, means closing the slot and covering the lightning arrester disposed therein, said lightning arrester including a pair of carbon resistors; and means electrically connecting one end of one of said resistors to one of said member-securing means and one end of the other of said resistors to the other member-securing means, and means electrically connecting the other ends of both of said resistors to said crosspiece.

3. In a high frequency television or frequency modulation antenna receiver installation which includes an electrically conductive mast and a rigid metallic driven element constituting at least two spaced members, a unitary device comprising a support for said driven element, said support including a rigid block of electrically non-conductive material, a pair of electrically conductive means detachably securing the members of said driven element to a face of said block in mutually spaced relationship, an electrically conductive crosspiece adapted to be detachably secured to the mast in electrical connection therewith, and a pair of electrically conductive bolts securing the crosspiece to the block on a face thereof opposite to the face on which the driven element is secured, said bolts extending through two openings in the block; said block having two spaced slots; a lightning arrester disposed concealedly in said block, said lightning arrester including a pair of carbon resistors, one

6 resistor being disposed in one slot and the other resistor being disposed in the other slot, one end of each resistor being secured to a different one of the bolts and the other end of each resistor being secured to one of the member-securing means, and mastic in the slots, said mastic covering the resistors.

EDWARD FINKEL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 395,956 Buck Aug. 11, 1908 2,240,298 Heindel et al Apr. 29, 1941 2,471,256 Wintermute May 24, 1949 OTHER REFERENCES Television & F. M. Antennas and Accessories, published by J. F. D. Manufacturing 00., Inc., copyright 1948, pages 9 and 14. 

